The Economist: The road to 270

Over the past two months, we have looked at the most important battlefield states where the presidential race will be decided. Put it all together, and what do you get?

HURRICANE SANDY smashed into a presidential race that was about as close as it could be. According to a constantly updated poll-of-polls published by the invaluable political website RealClearPolitics, the challenger, Mitt Romney, is now roughly tied with Barack Obama in the popular vote.

That tie, though, is essentially irrelevant, thanks to the Electoral College that allocates each state a number of votes in proportion to its size and (with two tiny exceptions) gives all of them to the candidate who wins most support there. As always, therefore, the battle has boiled down to just a few swing states. What is different this time is the narrowness of the margins in them.

Mr Obama, it is now clear, will not win any state he did not win in 2008, and is instead fighting hard to hold on to the gains he made then. Some states have been beyond his reach from the outset; Indiana, which rather improbably went Democratic in 2008, has never featured on anyone’s list of possible swing states this time round. And North Carolina, another longtime Republican state that Mr Obama managed to turn in 2008, has never really looked winnable for the president this time, though for just a few days in late September he did move fractionally ahead there. It is still, technically, a swing state (meaning that the average polling margin is less than 5%), but even though the Democrats went to the trouble of holding their party convention there no one now expects the president to take it.

In order to secure the presidency, a candidate needs to win 270 of the Electoral College’s 538 votes. States “worth” 201 votes can uncontroversially be assumed to go to Mr Obama, including such huge stalwarts as California and New York, and tiny ones such as Delaware and Rhode Island. For Mr Romney, states worth 191 votes between them are similarly locked up. Read more in The Economist